Rewiring 85 Pro line 20' CC What size wire needed??

gwgautney

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I am getting ready to rewire my boat completely. I was wondering what gauge wire do I need to run from battery to distribution block, dist. block to switch panel, and from switch panel to bilge pump,lights, and accessories. I know I need to get the tinned wire just not sure what size I need to go with.

Thanks
 

Bondo

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I am getting ready to rewire my boat completely. I was wondering what gauge wire do I need to run from battery to distribution block, dist. block to switch panel, and from switch panel to bilge pump,lights, and accessories. I know I need to get the tinned wire just not sure what size I need to go with.

Thanks

Ayuh,.... Ya need to figure out the largest possible load, on the D-box to figure what size wire to run from the battery,....

As for from the d-box to each appliance, 14ga. oughta be stout enough
 

Silvertip

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#8 or #10 gauge wire is typically used between the battery and the distribution (fuse) block. Heavier is better in this link as it provides a little wiggle room should you add more accessories later. I think you find that 14 gauge wire gets a little bulky when wiring closely spaced switches on a switch panel. Most every circuit on a boat can be wired with 16 gauge wire except for extremely high current draw items (such as a killer stereo system). Nothing inherently wrong with 14 gauge though except for bulk and the hit on your wallet. You need a suitable breaker in the positive lead within a foot of the battery. Lights, bilge pumps, standard radios (no amps), etc., all draw well under 10 amps and generally are fused between 5 and 7.5 amps which is well under the current handling capability of 16 gauge wire.
 

gwgautney

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Awesome thanks Silvertip. When you say breaker on positive lead ate you referring to online fuse? Or something different? I'm also going to install a battery selector switch while doing all of this.
 
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Silvertip

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If you are using a dual battery switch, then the feed to the distribution (fuse) block connects to the COM terminal on the switch. The large battery cable to the engine starter also connects to the COM terminal. The positive cable from each battery connects to the BAT #1 and BAT #2 terminals on the switch respectively. Both battery negative posts must be connected together and then the large negative cable goes to the engine block. There are many other creative wiring schemes for dual battery switches, but this technique is the simplest and practical. A circuit breaker replaces an in-line fuse just like a circuit breaker in house electrical panel replaced fuses decades ago. That breaker (normally 30 amp rating) in your application would go between the COM terminal on the switch and the #8 or #10 wire feeding the fuse block. It is required to protect that run of wire.
 

gwgautney

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ok cool I think I'm headed in the right direction. I am planning on pulling out everything this weekend. Going to do a little painting then rerun everything. I appreciate all the help. Anymore advice is greatly appreciated.
 

MH Hawker

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When i did mine a few years ago I used a 8 gauge for the run to the fuse panel and i ordered a 250 foot roll of 14 ga red and black to make things easier. I used the maxi ATC in line fuse holder 50 amp blade type because its at most any auto parts. I keep a spair 50 taped to the line by the holder and its ran to a 14 slot fuse block
 
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gwgautney

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what is the advantage of using tinned versus regular wire?
 
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